1. Field of the Invention
The present invention relates generally to a heat exchanger for an automotive vehicle. More particularly, the present invention relates to a tab for joining together a plurality of contiguous plates which are folded together to manufacture a plate-tube type heat exchanger.
2. Disclosure Information
Plate-tube type heat exchangers are well known in the art. In these types of heat exchangers, a plurality of elongated plates are joined together, such as through a lamination process to define a plurality of passageways for the movement of a fluid therethrough. Each of the passageways is formed by the inwardly facing surfaces of a pair of joined plates. The interior surfaces of the joined plates generally define a central fluid conducting section. The passageways are interconnected so that a fluid may flow through the plurality of joined plates forming the heat exchanger. As is also known in the art, conductive fin strips are located between outwardly facing surfaces of the pairs of joined plates. Heat exchangers of this type have particular utility as evaporators for air conditioning systems of motor vehicles.
Typically, plate-tube heat exchangers are manufactured by stacking a plurality of individual plates together to form a plate tube member and interleaving fin members between each tube member. Endsheets are then placed on opposite ends of the heat exchanger to form a heat exchanger core and the core is brazed in a furnace to complete the manufacturing process. Assembling the heat exchanger core in this manner is a labor intensive process requiring personnel to physically place individual plates in abutting face-to-face relationship to form the plate tube member.
One proposed method which may increase the productivity in fabricating plate-tube heat exchangers is shown in U.S. Pat. Nos. 3,258,832 and 3,344,925. These patents disclose a method of making a heat exchanger wherein a plurality of individual plates are stamped from a single sheet of material and interlinked together by tab members. The tab member is a straight piece of metal material which connects the plates and provides a location for bending to occur. After being formed, the plates are folded in a zig-zag formation to form a heat exchanger core. The tab member, however, bends at an undetermined location and cannot provide the most beneficial spacing for a fin member to be included between adjacent pairs of plate tubes and at the same time provide proper plate-to-plate contact.
It would be advantageous to provide a tab which can bend at different locations to provide for proper plate-to-plate contact when forming the plate tubes as well as to provide proper fin height spacing between adjacent pairs of plate tubes.